If you’ve ever been to the beach on a cloudy day and thought “I don’t need to put on sunscreen…there’s no sun!” then you probably have a pretty good idea. Just as you can get a wicked burn when it’s overcast, you can still get electricity from your solar system. Depending on the clouds, you can see your production drop off by a few points to a whopping 90%. And of course, at night, your system will be pretty much asleep.
But a really dark and stormy day isn’t as much of a factor as your climate throughout the year. Most people with solar are still connected to the grid, so they buy power when they need more than they have, and sell back when they’re producing more than they need. Battery backup is also an option–albeit a pretty expensive one–for on and off-grid living. Your system charges your batteries while the sun is shining, and uses them up when it’s not. Just make sure your utility buys back at a fair price or you won’t save much money at all.